Forged dipper tooth



LSQQQQ? Dec. E3, 1932. A. R LANE I FORGED DIPPER TOOTH Filed May 25 1932 Patented Dec. 13, 1932 UNITED STATES AUBREY B. LANE,

PATENT OFFICE 01' OHIGAGOQIIILINOIS, ASSIGNOB A. FIRE & SONS OOIPANY, OI CHICAGO, ILLINOIS, A CORPORATION 01' ILLINOIS roman mrrna 'roo'rn Application filed Kay 25,

'vide a simple and improved form of tooth and base that can be made by the forging process, and requiring a minimum amount of additional machining.

Detachable dipper teeth are preferably made of abrasion-resisting alloys which are compartively diiiicult to machine, so that most of such devices have heretofore been formed of castings which include, so far. as practicable, the interlocking joint structure for connecting the teeth to their'base, thereby avoiding as much machining as possible. Consequently, practically all forms of cast dipper teeth now in commercial use are of such comparatively complicated designs that they would not be commercially practicable if made by other manufacturing processes, such as forging.

In carrying out my invention, I provide a novel and simple construction of dipper tooth and base especially designed for forging, and requiring a minimum amount of machining. When so constructed, my. improved form of tooth is more economical in manufacture and use, and less subject to breakage than teeth now on the market.

The invention may best be understood by reference to the accompanying drawing, in which Figure 1 is a fragmentary side view of a dipper tooth and base assembly, constructed in accordance with my invention.

Figure 2 is a detail section taken on line 22 of Figure 1.

Figure 3 is a top plan view of the tooth removed from the base.

Referring to details of the embodiment of my invention shown in the drawing, 10 indicates the projecting portion of a tooth base, which is secured to the dipper (not shown) in the usual manner. The detachable tooth is indicated generally at 11, and comprises a head 12 and a shank 13. The head 12 is formed with two plane upper and lower faces 14, 14 converging forwardly to the point of the tooth, and two parallel plane side faces 15, 15. The head 12 also has two 1988. Serial R0. 613,587.

rearwardlyconverging faces 16, 16 which meet the rearward edges of the forwardly converging faces 14 at a relatively sharp angle, and merge into the shank 13-at the center and into each other alon the rounded edges 17, 17 extending latera 1y, at opposite sides of said shank.

A pair of interlocking ribs 18, 18 are formed as elevations alon the center of each rear face 16, and longitudinally of the major axis of the tooth, said ribs being generally tapered outwardly in cross section, as is best shown in Figure 3.

The shank 13 is cylindrical in shape, extending rearwardly from the head with its axis coinciding with the major axis of the latter. through the rear end of said shank, for engagement by a wedge pin 20, as shown in Figure 1. In the form shown, the aperture h is elongated in the direction of the major axis of the shank and has, in addition, a pair of slots 19*, 19 formed along opposite forward walls thereof, for a purpose that will presently appear.

Referring now generally to the formation of the tooth, it will be observed that the several parts are arranged symmetrically with respect to the median plane of the tooth, including its major axis and the meeting edges of the front faces 14, 14 as indicated by line AA in Figure 1, so that the tooth is fully reversible and can be forged with identical upper and lower forging dies. The front and rear converging faces. 14 and 16, respectively, are both inclined at an obtuse angle to thecentral plane of the tooth so as to make an especially solid, compact and simple forging. The opposite. sides of the head 12, shank 13 and ribs 18 are all either curved or tapered inwardly from the median plane, so that all the parts can be readily formed to final shape during a single forging operation. Practically the only machining necessary for finishing the entire tooth is that of trimming the flash and forming the wedge pin aperture 19 with its slots 19*, 19, in the shank.

The base 10 is provided with corresponding interlocking surfaces for receiving the tooth, including a circular bore 13 to receive the shank 13, inwardly converging walls 16, 16 to receive the rear walls 16, 16 in seated enga ement, and grooves 18, 18 in which therlbs 18, 18 have close fitting engagement. These surfaces may be readily machined on the base, the bore 13" being drilled in a single operation, and the surfaces 16 and 18 being finished with a simple machining'process such as milling, shapmg or slotting.

- The tooth 1s held in place by the wedge pin 20 passing through a tapered aperture 21 formed in the base 10 and registering with the aperture 19 in the shank 13 when the tooth and base are in assembled position as shown in Figure 1.

In order to hold the wedge pin in place, a locking pin 21 is seated in a bore 22 formed in the front face of said pin. Said pin is normally urged forwardly by a compression spring 23 seated against the bottom of the bore 22. The arrangement is such that the locking pin may be pushed inwardly to permit insertion of the wedge pin, but when the latter reaches its seated position, the locking pin registers with one of the slots 19' formed in shank 13, and isautomatically sprung outwardly into lockin position beneath the adjacent side wall of the bore 13", thus securely holding said wedge pin in place. In the event that the wedge pin is to be removed, the latter ma be knocked out under sufficient force to s ear the looking pin.

t will be observed, that the tooth 11 is fully reversible with regard to its seat in the base, that is to say, it can be fitted in a position inverted from the position shown in Figure 1.

Although I have illustrated and described one particular embodiment of my invention, it will be understood that I do not wish to be limited to the exact construction shown and described, but that various changes and modifications may be made without departing from the spirit and scope of my invention.

I claim:

1. A dipper tooth including a base and a removable tooth, said tooth consisting of a head and a rearwardly projecting shank, said head having upper and lower faces converging to form the point of said tooth, and rearwardly inclined faces merging into said shank 'at an obtuse an le to the major axis of said 7 said dipper tooth to said base.

2. A dipper tooth including a base and a removable tooth, said tooth consistin of a head and a rearwardly projecting shan said head having upper and lower faces converging to form the point of said tooth, and rearwardly inclined faces merging into said shank at an obtuse angle to the major axis of said tooth, said shank being substantially circular in cross section, a pair of ribs formed at the meeting angles 0 and merging into said shank and rear faces, and extending outwardly to the ed es thereof, said base having a socket inclu ing a circular bore for receivin said shank, and grooves for receiving sai ribs in close fitting engagement, and a pin extending through said base and said shank for securing said dipper tooth to said base.

3. A removable dipper tooth adapted to be formed by forging, which consists of a head and rearwardly projecting cylindrical shank, said head having forward top and bottom faces converging to form the point of said tooth, rearwardly inclined plane faces merging into said shank, a pair of ribs extending outwardly and centrally along the length of said rear faces and merging into said shank, said shank having a transversely extending aperture adjacent its rearward end for receivinga securing pin.

' Si ned at Chicago, Illinois, this 17th day of ay, 1932.

AUBREY R. LANE. 

